Optical glass is an indispensable important part in optical equipment and photoelectric products. In the wake of widespread popularity of photoelectric products such as smart phone and SLR camera in recent years, higher requirements are proposed for the performance of the optical glass, for example, the optical glass is required to have the performance of eliminating all or part of the residual chromatic aberration of the secondary spectrum to the best extent possible, thus it is necessary for optical glass to provide a negative anomalous dispersion performance.
At present, the known optical glass with the negative anomalous dispersion performance adopts B2O3—Al2O3—PbO system, but the content of PbO in the glass of such system is larger, so the chemical stability of the glass is poor, and the environmental requirements cannot be met. For the glass system containing no PbO in the Chinese patent with the Publication No. of 1225903, the German patent with the Publication No. of 4032566, the Chinese patent with the Publication No. of 102199001 and the United States patent with the Publication No. of 4200467, Ti or F, which is an element destroying the anomalous dispersion performance, is introduced to these glass, or these glass contains more Nb2O5, which also destroys the anomalous dispersion performance of glass. In addition, U.S. Pat. No. 4,200,467 contains a higher proportion of Na ion, but this will result in serious fractures to the glass structure, increasing glass devitrification trend, and be extremely unfavorable for the expansion coefficient, heat stability, chemical stability and mechanical strength of the optical glass.